Export Process

OpenCPN User Manual - 2 Versions

Full version

Duplicate of the Full User Manual that is on the Website.
Which has had the image files optimized by OptiPNG, approximately 20mb.

Condensed Version

The Condensed Version has been reduced in size and the images have been compressed more. May be preferred by users of smaller slower computers, approximately 10.5 mb.

Note: Both version contain the External Plugins documentation.

Full Version Processing

This document describes how the User Manual is moved to the Opencpn/Opencpn wiki and compressed.

It includes some rules. When Pavel and David create the install software they download a copy of the manual and process the images with optipng. Then include the html file as aa part of the software 'Help'.

User Manual Export OpenCPN User Manual

Run all pictures in the folder “OpenCPN User Manual_files” through “optipng”optipng
Open a commandline in the folder and run $optipng -o7 *.png

This does not result in much compression or savings of space. For example 44 mb —> 38 mb

Pavel has a script to convert images >=100kb to Jpeg and optimize. It is not clear at this point how much resize and compression he is using.
https://github.com/nohal/OpenCPNScripts/blob/master/doc_fix.sh

This script is using mozpeg see
https://hacks.mozilla.org/2014/08/using-mozjpeg-to-create-efficient-jpegs/

Also see Mozpeg 3.0
http://calendar.perfplanet.com/2014/mozjpeg-3-0/

Here is a sample file of each level of compression: see 70 and 50
http://blog.mozilla.org/hacks/files/2014/07/JPEG-Quality-Comparison.png

Also the script shows that he is converting to 32 bit color.
The script is also using 'gm' to optimize the remaining png, which I believe is Graphics Magick.
http://www.graphicsmagick.org/

Also See https://github.com/OpenCPN/OpenCPN/tree/master/data/doc

Condensed Version Processing

1. Does not contain these pages:

2. To Skip the namespaces above add them to the “skipns” parameter for the indexmenu on the OpenCPN Embedded User Manual. See Site Export Plugin. NOTE: BELOW THIS NEEDS REVIEW FOR THE NEW DOKWIKI

3. From the Browser User Manual Export OpenCPN User Manual

4. Download the Condensed Version by using your Browser's File > Save Page As NOTE FROM HERE DOWN IS OK.

5. Compress the User Manual image files with FastStone Photo Resizer * Convert from PNG& GIF to JPG

6. Details for using FastStone Photo Resizer
Use FastStone Photo Resizer Batch process: convert, resize & compress

In the main window check “Keep original date/time” and “Ask before overwrite”.
Output Format: Select Jpeg Settings: Pick Quality 50 or 70
Output Folder: Browse to your output folder, select it.
In the main window “Pick All files”
Then “Convert”

Compressed Sizes

Condensed User Manual Image files
728 files, 44.5 mb —→ 12.7 mb at Jpeg Compression 70 Good Quality.
Total Expected size HTML 900 kb + 12.7 mb = 13.6 mb. I believe this is slightly less than v4.0

Condensded Alterrnative Image fles
728 files, 44.5 mb —→ 9.3 mb at Jpeg commpression 50. Still very legible.
Total Expected size HTML 900 kb + 9.3 mb = 9.26 mb. I believe this is 65% less than v4.0

Full User Manual Image files (Website Version)
46.7 mb —> 12.5 mb using FastStone at Jpeg compression 70 Good Quality 46.7 mb —> 9.5 mb using FastStone at Jpeg compression 50 Still very legible.
46.7 mb —> 17 mb using Mozpeg for photos >100kb and using OptiPNG $ optipng -o7 *.png
Estimated: Top 106 files, 24mb Png —>3mb JPG Size width=525 Compression=70 Color=32
Estimated: Other optimized 640 Png —>14mb png
Total: 17mb

8. Availability
The Condensed version will be available on OpenCPN Download or OpenCPN Beta File Thingie.